News by Date
News by Category
Solar System
Stars
White Dwarfs
Supernovas
Neutron Stars
Black Holes
Milky Way Galaxy
Normal Galaxies
Quasars
Galaxy Clusters
Cosmology/Deep Field
Miscellaneous
Press Resources
Status Reports
Press Advisories
Image Releases
Release Guidelines
Image Use Policy
NASA TV
Biographies/Interviews
Web Shortcuts
Chandra Blog
RSS Feed
Chandra Mobile
Chronicle
Email Newsletter
News & Noteworthy
Image Use Policy
Questions & Answers
Glossary of Terms
Download Guide
Get Adobe Reader
Chandra @ NASA
Visit the Chandra pages at the NASA portal
Image Use
Image Use Policy & Request Form
Guidelines for utilizing images, applets, movies, and animations featured in this Web Site.
Getting Hard Copies of Images
Ways to obtain photos, slides, etc of Chandra images.
Operations CXO Status Report

Wednesday 18 August 1999 7.00am EST

The following is an overview of the events that occurred over the last 24 hours.

While executing mission sequence load number 3, Chandra entered Safemodes. Initial analysis indicated that the reason for safemode entry was because the Offline System scheduled back to back segmented maneuvers to close together such that the first maneuver did not properly settle out before the second maneuver started. This caused an attitude rate error, which resulted in a successful safemode entry. Redundancy management processes transferred control to B-Side hardware, PCAD control was transferred to the Command Processing Electronics (CPE) assembly, B side On Board Computer (OBC) assumed thermal control and power management, and the ISIM translated (for the first time) to the mid-point safe position. On-site Operations personnel, and members of the Technical Support Team are carefully reviewing and testing recovery procedures on the Test Bed. Safemode recovery on the spacecraft is scheduled to be initiated at 1:30pm EDT today.

Activities for next 24 hours: Recover from Safemode and continue performing SCS directed on-orbit operations.





Return to Status Reports